The knowledge concerning psoriasis has literally exploded in recent years, leading to a new science-based disease management. The focal point of these developments lies in biological immunotherapy, which provides much promise for the future. This up-to-date book, written by authors with a profound knowledge of the science and practice of psoriasis, has a clear emphasis on the treatment options available. Wherever possible, evidence is presented when describing the use of these agents and recommendations based on high-level guidelines are cited. This textbook also includes a chapter on psoriatic arthritis, an associated disease which has a major impact on the quality of life in patients and has a direct effect on treatment choices. Finally, a chapter on the Psoriasis Area and Severity Index (PASI) is featured, which will be valuable to all clinical dermatologists who are not familiar with this technique for quantifying psoriasis.